OBJECTIVE: Group activities are commonly offered to residents of nursing homes, and increasingly with a person-centred care approach. The aim of this study is to compare the impacts of a Montessori-based reading activity with a more traditional reading activity.
METHODS: A multiple baseline design was used, with 3 groups of 5 older adults with moderate to severe dementia. All sessions were videorecorded and analysed by independent judges, blinded to our hypotheses and conditions. Impacts of the type of activity (storytelling or Montessori-based reading) on verbal interactions, engagement level, affect and behavioural aspects were estimated with both visual analyses and statistical analyses using the between-case standardised mean differences method.
RESULTS: Significant differences were found in favour of the Montessori-based activities with regard to the number of verbal interactions, constructive and passive engagement and positive affect expressed, with moderate to large effect size (from 0.46 to 1.66).
CONCLUSIONS: The Montessori-based reading group activity really seems to be preferable to a more traditional storytelling activity, with multiple benefits for residents. Depending on the preserved abilities and interests of the participants, it can also be aimed at people with severe dementia.

This review evaluated single-case experimental design research that examined challenging behavior interventions utilizing punishment elements. Thirty articles published between 2013 and 2022 met study inclusion criteria. Study quality was also assessed. Through multiple levels of analysis (e.g., descriptive statistics, non-parametric statistics), we examined (a) participant and study trends, (b) differential outcomes related to temporal reinforcement approaches (antecedent, consequent, or combined reinforcement) applied alongside punishment element(s), (c) differential outcomes related to the punishment type (negative, positive) applied alongside reinforcement, and (d) effect sizes associated with study rigor across peer-reviewed and gray literature. Our results may tentatively suggest that, for certain situations, concurrently applying punishment with antecedent reinforcement approaches may coincide with significantly larger effect sizes compared to combined temporal reinforcement approaches, while positive punishment applied concurrently with reinforcement may coincide with larger but non-significant intervention effects. Most featured articles met rigor criteria, but larger effects were seen in peer-reviewed literature.

Generalized linear mixed models (GLMMs) have great potential to deal with count data in single-case experimental designs (SCEDs). However, applied researchers have faced challenges in making various statistical decisions when using such advanced statistical techniques in their own research. This study focused on a critical issue by investigating the selection of an appropriate distribution to handle different types of count data in SCEDs due to overdispersion and/or zero-inflation. To achieve this, I proposed two model selection frameworks, one based on calculating information criteria (AIC and BIC) and another based on utilizing a multistage-model selection procedure. Four data scenarios were simulated including Poisson, negative binominal (NB), zero-inflated Poisson (ZIP), and zero-inflated negative binomial (ZINB). The same set of models (i.e., Poisson, NB, ZIP, and ZINB) were fitted for each scenario. In the simulation, I evaluated 10 model selection strategies within the two frameworks by assessing the model selection bias and its consequences on the accuracy of the treatment effect estimates and inferential statistics. Based on the simulation results and previous work, I provide recommendations regarding which model selection methods should be adopted in different scenarios. The implications, limitations, and future research directions are also discussed.

Recent publications within Contextual Behavioral Science provided a rationale for the expansion of intervention efficacy research using methods that capture idiographic factors and processes. We conducted a systematic review of the use and quality of single-case experimental designs (SCED) within the Acceptance and Commitment Therapy (ACT) literature in adult clinical populations. The systematic review was conducted according to PRISMA guidelines and the databases CINAHL, MEDLINE, PsycINFO, PsycArticles and OpenGrey were searched for peer-reviewed articles. Further studies were sought through review of reference lists of all full text studies. Studies were assessed against What Works Clearinghouse (WWC) single-case design standards. Twenty-six studies met eligibility criteria and were conducted within research teams all implementing multiple-baseline designs. Twenty-four studies did not meet WWC standards with most failing to ensure a degree of concurrence across participants. The extent of randomisation methods was also captured. The review highlights the sparsity of SCEDs within ACT literature in clinical populations and current methodological practices. Limitations of the review and implications for future research are discussed.

BACKGROUND: Hematopoietic cell transplantation (HCT) is a highly invasive and life-threatening treatment for hematological neoplasms and some types of cancer that can challenge the patient\'s meaning structures. Restoring meaning (i.e., building more flexible and significant explanations of the disease and treatment burden) can be aided by strengthening psychological flexibility by means of an Acceptance and Commitment Therapy (ACT) intervention. Thus, this trial aims to examine the effect of the ACT intervention on the meaning-making process and the underlying mechanisms of change in patients following HCT compared to a minimally enhanced usual care (mEUC) control group. The trial will be enhanced with a single-case experimental design (SCED), where ACT interventions will be compared between individuals with various pre-intervention intervals.
METHODS: In total, 192 patients who qualify for the first autologous or allogeneic HCT will be recruited for a two-armed parallel randomized controlled trial comparing an online self-help 14-day ACT training to education sessions (recommendations following HCT). In both conditions, participants will receive once a day a short survey and intervention proposal (about 5-10 min a day) in the outpatient period. Double-blinded assessment will be conducted at baseline, during the intervention, immediately, 1 month, and 3 months after the intervention. In addition, 6-9 participants will be invited to SCED and randomly assigned to pre-intervention measurement length (1-3 weeks) before completing ACT intervention, followed by 7-day observations at the 2nd and 3rd post-intervention measure. The primary outcome is meaning-related distress. Secondary outcomes include psychological flexibility, meaning-making coping, meanings made, and well-being as well as global and situational meaning.
CONCLUSIONS: This trial represents the first study that integrates the ACT and meaning-making frameworks to reduce meaning-related distress, stimulate the meaning-making process, and enhance the well-being of HCT recipients. Testing of an intervention to address existential concerns unique to patients undergoing HCT will be reinforced by a statistically rigorous idiographic approach to see what works for whom and when. Since access to interventions in the HCT population is limited, the web-based ACT self-help program could potentially fill this gap.
BACKGROUND: ClinicalTrials.gov ID: NCT06266182. Registered on February 20, 2024.

The use of single-case experimental design (SCED) to evaluate cognitive remediation is growing. SCEDs require rigorous methodology and appropriate choice of primary outcomes. To review primary outcomes that assess executive function impairments in patients with acquired brain injury (ABI). A scoping review was conducted using the Arksey and O\'Malley framework and the PRISMA extension for scoping review (PRISMA-ScR). Five databases were searched resulting in the inclusion of twenty-one studies. Primary outcomes were extracted and classified according to the type of measure, ecological setting and sources of possible bias. A wide variety of primary outcomes were identified; the majority of which evaluated behavioural performance during a real-life activity or in a real-life simulated setting. The most frequent bias observed across outcomes was the coaching effect. The findings of this scoping review highlight the importance of selecting appropriate outcomes for repeated measures in SCED studies. Direct observation of the target behaviour is a potential gold standard for assessing the effectiveness of a cognitive intervention.

Our objective is to implement a single-case experimental design (SCED) infrastructure in combination with experience-sampling methods (ESM) into the standard diagnostic procedure of a German outpatient research and training clinic. Building on the idea of routine outcome monitoring, the SCED infrastructure introduces intensive longitudinal data collection, individual effectiveness measures, and the opportunity for systematic manipulation to push personalization efforts further. It aims to empower psychotherapists and patients to evaluate their own treatment (idiographic perspective) and to enable researchers to analyze open questions of personalized psychotherapy (nomothetic perspective). Organized around the principles of agile research, we plan to develop, implement, and evaluate the SCED infrastructure in six successive studies with continuous stakeholder involvement: In the project development phase, the business model for the SCED infrastructure is developed that describes its vision in consideration of the context (Study 1). Also, the infrastructure\'s prototype is specified, encompassing the SCED procedure, ESM protocol, and ESM survey (Study 2 and 3). During the optimization phase, feasibility and acceptability are tested and the infrastructure is adapted accordingly (Study 4). The evaluation phase includes a pilot implementation study to assess implementation outcomes (Study 5), followed by actual implementation using a within-institution A-B design (Study 6). The sustainability phase involves continuous monitoring and improvement. We discuss to what extent the generated data could be used to address current questions of personalized psychotherapy research. Anticipated barriers and limitations during the implementation processes are outlined.

There are numerous effect measures researchers can select when conducting a meta-analysis of single-case experimental design research. These effect measures model different characteristics of the data, so it is possible that a researcher\'s choice of an effect measure could lead to different conclusions about the same intervention. The current study investigated the impact of effect measure selection on conclusions about the effectiveness of check-in check-out (CICO), a commonly used intervention within School-Wide Positive Behavior Interventions and Supports. Using a multilevel meta-analysis of seven different effect measures across 95 cases in 22 studies, findings suggested that all effect measures indicated statistically significant results of CICO in improving student behavior. However, the magnitude of the effects varied when comparing the results to interpretive guidelines, suggesting that the selection of effect measures may impact conclusions regarding the extent to which an intervention is effective. Implications, limitations, and future directions are discussed.

Count outcomes are frequently encountered in single-case experimental designs (SCEDs). Generalized linear mixed models (GLMMs) have shown promise in handling overdispersed count data. However, the presence of excessive zeros in the baseline phase of SCEDs introduces a more complex issue known as zero-inflation, often overlooked by researchers. This study aimed to deal with zero-inflated and overdispersed count data within a multiple-baseline design (MBD) in single-case studies. It examined the performance of various GLMMs (Poisson, negative binomial [NB], zero-inflated Poisson [ZIP], and zero-inflated negative binomial [ZINB] models) in estimating treatment effects and generating inferential statistics. Additionally, a real example was used to demonstrate the analysis of zero-inflated and overdispersed count data. The simulation results indicated that the ZINB model provided accurate estimates for treatment effects, while the other three models yielded biased estimates. The inferential statistics obtained from the ZINB model were reliable when the baseline rate was low. However, when the data were overdispersed but not zero-inflated, both the ZINB and ZIP models exhibited poor performance in accurately estimating treatment effects. These findings contribute to our understanding of using GLMMs to handle zero-inflated and overdispersed count data in SCEDs. The implications, limitations, and future research directions are also discussed.

People with primary psychosis are among the most seen in inpatient psychiatry. Treatment guidelines recommend both pharmacological and psychological treatments. However, psychological treatments are not routinely offered in many settings. There is also a lack of research on psychological treatments for this vulnerable population in the inpatient setting. The first aim of the current study was to examine treatment effects of a brief form of Acceptance and Commitment Therapy on outcomes valued by the treatment recipients. The second aim was to explore hypothetical processes of change in relation to outcomes over time. Three people with primary psychosis were treated for two to four sessions. A replicated single-case experimental design with multiple baselines across subjects (Clinical Trials registration number ID NCT04704973) was employed to examine treatment effects. The Personal Questionnaire (PQ) was used as primary outcome, symptom believability and preoccupation as proposed processes of change. Data were analyzed using visual inspection, calculation of Tau-U values, and cross-lagged correlation. All participants improved significantly on PQ and the symptom preoccupation measure. Two improved significantly on the symptom believability measure. Cross-lagged correlation analyses showed no clear mediation. Change in proposed processes of change and primary outcome predominantly happened concomitantly, although patterns of results reflected individual differences.